Conventionally, in order to allow information equipment to be usable in the operating system (hereinafter referred to as “OS”) of a personal computer (hereinafter referred to as “PC”), a driver for the use of the information equipment on the OS must be installed on the OS. An example of a method for installing the driver includes Plug and Play Extensions (hereinafter referred to as “PnPX”) (see Non-Patent Documents 1 and 2). The PnPX is a standard function that is preinstalled in the Windows (registered trademark) Vista OS and is a technology in which the OS acquires and installs a driver for the information equipment present on the network in a unique manner upon reception of a user's command. Also, in the PnPX, a scheme in which the OS finds the information equipment on the network, which is called “Web Services on Devices” (hereinafter referred to as “WSD”), is employed (see Non-Patent Document 3). Furthermore, examples of a method for causing the OS to acquire a driver when performing the PnPX include a method for acquiring a driver by searching the hard disk on the PC, a method for acquiring a driver from a Web server dedicated for the OS arranged on the internet, and the like. Note that some information equipment may have an appearance of a single information equipment but may be internally configured by a plurality of information equipment. For example, in spite of having an appearance of a single information equipment, such information equipment may internally incorporate a plurality of information equipment such as a printer, a scanner, a FAX, and the like. Such information equipment may be referred to as a “Multi Function Printer” or a “multipurpose machine”.
When the PnPX occurs on the aforementioned multipurpose machine, a driver is required for each of a plurality of information equipment that is present internally. For example, in the case of a multipurpose machine in which a printer and a scanner are preinstalled, the two types of drivers, i.e., the driver for the printer and the driver for the scanner, are installed by the PnPX. Here, when taking developers and a driver distribution method mainly into consideration, a driver can be classified into three types as follows. A first type is an OS standard driver developed by an OS development company such that the minimum function of information equipment can be employed. This OS standard driver is available for many of the general information equipment such as a printer, a FAX, and the like. A second type is a full specification driver uniquely developed by information equipment development company (THY) such that all of the functions of information equipment can be employed on the OS. IHV is an abbreviation for Independent Hardware Vendor. In general, since only the minimum necessary functions for information equipment are preinstalled among the standard OS drivers, any unique functions packaged in information equipment by each IHV cannot be employed. Hence, it is desirable that a full specification driver be installed. However, in general, a user needs to search and obtain a full specification driver by himself, and thus considerable time and labor are required. Also, it may be difficult for a user to know how to acquire a full specification driver. Furthermore, in the case of a multipurpose machine, a plurality of drivers needs to be acquired depending on the number of the preinstalled information equipment, which may be difficult to be understood by a general user. A third type is an OS-provided driver provided from the IHV to the OS development company in order to solve the problem that the aforementioned user has difficulty in acquiring a full specification driver. The OS development company stores the provided OS-provided driver in a location where the OS can recognize, whereby the OS can install an IHV-made OS-provided driver upon execution of the PnPX.
A limitation is often placed on the OS-provided driver. A representative example of such limitation includes a capacity limitation. The OS-provided driver is often stored mainly on the hard disk of the PC or is often stored on the Web server dedicated for the OS arranged on the internet. However, if the IHV-made full specification drivers for all kinds of the information equipment are stored on the hard disk or the Web server dedicated for the OS, a very large amount of capacity is required, resulting in a great burden on the PC or the Web server. Hence, a limitation may be placed on the capacity of a driver. To satisfy the capacity limitation, some of the functions of the OS-provided driver may be deleted compared with those of the full specification driver. Thus, installation of the OS-provided driver may cause a problem in that a user cannot use all of the functions of the information equipment. In order to deal with the problem, a technique in which the OS downloads and installs a full specification driver by executing the PnPX module developed by the IHV has been proposed. For example, Patent Document 1 discloses a program that determines that either the performance information for a printer discovered by the WSD module or the performance information for a printer currently installed has a higher priority and installs a driver in accordance with the determination result.